Research

Hormonal

Cortisol circadian rhythm contributes to decreased insulin sensitivity in the evening, as elevated morning cortisol is associated with high insulin sensitivity, while lower evening cortisol coincides with reduced sensitivity.

Your natural cortisol rhythm affects how sensitive your cells are to insulin. Morning cortisol helps keep you sensitive, while the natural drop in the evening contributes to reduced sensitivity. This is a normal physiological pattern, not necessarily a sign of 'stress' in the negative sense.

GoodQualifiesMEDIUM confidence
Thus, under physiological conditions, the circadian variation of cortisol concentrations is likely to be a causal mechanism for optimal glucose tolerance with minimal insulin-secretory responses in the morning and diminished insulin sensitivity without appropriate increases in insulin secretion 6 –15 h later, i.e., in the afternoon and evening.
Eve Van Cauter et al. · Endocrine Reviews · 1997

Why this rating

Based on studies using CRH/hydrocortisone administration (Ref 58) and correlation with glucose patterns.

Source

Roles of Circadian Rhythmicity and Sleep in Human Glucose Regulation*

Eve Van Cauter et al. · Endocrine Reviews · 1997

DOI 10.1210/edrv.18.5.0317

narrative_reviewCited 580×
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DOI resolved against Crossref · corpus check 2026-06-10

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